Liebermann J, Schams D, Miyamoto A
Institute for Physiology, Research Center for Milk and Food, Technical University Munich, Freising-Weihenstephan, Germany.
Reprod Fertil Dev. 1996;8(6):1003-11. doi: 10.1071/rd9961003.
The impact of insulin-like growth factor-I (IGF-I) basic fibroblast growth factor (bFGF), endothelin-1 (ET-1), tumour necrosis factor-alpha (TNF-alpha), transforming growth factor-alpha (TGF-alpha) and platelet-derived growth factor (PDGF) on the release of progesterone (P4) and oxytocin (OT) from individual bovine corpora lutea at different stages of the oestrous cycle and pregnancy was evaluated with a microdialysis system (MDS) in vitro. IGF-I (1 microgram mL-1) induced significantly the acute effects on P4 release at the late luteal stage (Days 15-18) and early pregnancy (Days 60-120), whereas bFGF (100 ng mL-1) was extremely effective in stimulating P4 release particularly during the mid-luteal stage (Days 8-12). Both peptides stimulated (P < 0.05) the release of OT throughout the three luteal stages and during early and late pregnancy (Days 30-60 and Days 150-210). ET-1 (100 ng mL-1) clearly inhibited P4 release during the early (Days 5-7) and mid-luteal phase and stimulated OT release only during the mid-luteal stage (P < 0.001). TNF-alpha (100 ng mL-1) stimulated the release of P4 exclusively at the early luteal phase (P < 0.05), whereas OT secretion was increased by TNF-alpha during all stages of the oestrous cycle (P < 0.001). TGF-alpha and PDGF (100 ng mL-1) were effective in stimulating P4 release particularly during late pregnancy (P < 0.05). In contrast, stimulation of OT secretion by TGF-alpha was maximal during the late-luteal stage (P < 0.001), whereas PDGF significantly increased OT secretion during the oestrous cycle (except the early luteal stage) and pregnancy (P < 0.001). The data demonstrate distinct and stage-specific effects of growth factors on P4 and OT secretion in vitro. IGF-I, bFGF and TGF-alpha may play an important role in corpus luteum (CL) function during the oestrous cycle and pregnancy since they are locally expressed and synthesized, there are receptors for these growth factors, and they have been demonstrated to exert biological effects on the CL.
采用微透析系统（MDS）在体外评估胰岛素样生长因子-I（IGF-I）、碱性成纤维细胞生长因子（bFGF）、内皮素-1（ET-1）、肿瘤坏死因子-α（TNF-α）、转化生长因子-α（TGF-α）和血小板衍生生长因子（PDGF）对处于发情周期和妊娠不同阶段的单个牛黄体释放孕酮（P4）和催产素（OT）的影响。IGF-I（1微克/毫升）在黄体后期（第15 - 18天）和妊娠早期（第60 - 120天）对P4释放有显著的急性诱导作用，而bFGF（100纳克/毫升）在刺激P4释放方面极其有效，尤其是在黄体中期（第8 - 12天）。这两种肽在整个三个黄体阶段以及妊娠早期和晚期（第30 - 60天和第150 - 210天）均刺激（P < 0.05）OT的释放。ET-1（100纳克/毫升）在黄体早期（第5 - 7天）和中期明显抑制P4释放，且仅在黄体中期刺激OT释放（P < 0.001）。TNF-α（100纳克/毫升）仅在黄体早期刺激P4释放（P < 0.05），而在发情周期的所有阶段TNF-α均增加OT分泌（P < 0.001）。TGF-α和PDGF（100纳克/毫升）在刺激P4释放方面有效，尤其是在妊娠后期（P < 0.05）。相比之下，TGF-α对OT分泌的刺激在黄体后期最大（P < 0.001），而PDGF在发情周期（除黄体早期）和妊娠期间显著增加OT分泌（P < 0.001）。数据表明生长因子在体外对P4和OT分泌具有独特的阶段特异性作用。IGF-I、bFGF和TGF-α可能在发情周期和妊娠期间的黄体（CL）功能中起重要作用，因为它们在局部表达和合成，存在这些生长因子的受体，并且已证明它们对CL发挥生物学作用。
